Hairdos which must be dried uniformly so that curls and waves are not dissolved, or disarrayed, by a concentrated, or forceful, air flow, require a special type of hair dryer.
Existing hair dryers are commonly known to provide drying through creation of a concentrated air flow of high blow, or velocity, through a relatively small blow opening, transporting heated air to reach the individual hairs in order to dry the hair in the shortest possible time. Such hair dryers are not acceptable for the stated purpose of drying hair curls and waves without effecting their disarray.
Other hair dryers have sought to meet the stated problem. Such other dryers use a blow opening of relatively large diameter, in an attempt to obtain a wide dispersal of the air flow. Such dryers are usually provided with an electromotor that, because of its size, awkwardly reaches completely out of the backside of the hair dryer, and with an air-driving propeller, or blower, positioned in the casing for blowing air over a wound heating wire for heating the air. One principal disadvantage of such a dryer, in addition to its large size making it difficult to manipulate, lies in the fact that it uses a wound heating wire as the source of convection heat. The radiant heat from such a heating wire is only superficial, and in order to obtain real drying, the blower must work at high speed and this produces the undesirable effect that the hairdo is subjected to turbulence from the moving air and thus is subject to destruction or disarray.
It is also known, generally, to use infra-red heat sources for hair drying. The infra-red heat sources, of known and marketed hair dryers, is a lamp. It is evident that the dimension of such an embodiment will be relatively large, because in order to obtain a satisfactory heating source, the body of the lamp, consisting of a coil in a vacuum space, must be made large. With such a source of infra-red heat, the instrument becomes difficult to handle, clumsy and top-heavy, and its use in a practical manual operation cannot be obtained. Furthermore, an instrument of this type has a maximum efficiency of only about 150 watts.
Other infra-red radiators are known in embodiments for the purpose of hair drying, such radiators being mounted on a stand so that they are used exclusively as standing equipment.
In connection with hair drying, it has been determined that infra-red radiation provides radiation heat which, through the process of absorption, transforms the radiation into heat at or adjacent the surface of the hair. The existence of the outer surface of the hair mass interferes with penetration of the infra-red heat through the thick mass of hair. To avoid absence of radiation heat below the outer surface of the hair mass, a slight, or soft, blowing of air in combination with infra-red radiation will move outer portions of hair gently, which permits the infra-red radiation to penetrate into the hair mass and to avoid radiation shadows. However, it has also been observed that the flow of room-temperature air through the means of an air blower can create an unpleasant cooling effect in wet or moist hair.
Therefore, a principal object of the present invention is to create an improved, infra-red, hair dryer for air-drying hairdos, which dryer avoids the above-mentioned disadvantages, and which will be used primarily as a hand-held instrument.
The infra-red hair dryer of this invention is particularly practical, being small and lightweight but having a relatively high heat output of up to 500 watts, producing little or no noise, having high efficiency, and in which the functional form also meets the requirements set forth for an electrical cosmetic instrument.
Another object of this invention is to provide a hand-held hair dryer wherein the primary source of drying is infra-red radiation, in combination with air-moving means for gently moving portions of the hair to permit penetration of radiant heat through the depth of the hair mass, and with means for convection heating the air being moved, so as to avoid unpleasant cooling effect of the moving air while also aiding, in some measure, the drying of the hair.
A further object of this invention, in connection with the use of both a primary infra-red radiation source and a secondary heater for modest heating of the air moved by a blower of the dryer, is to provide use of at least one of those heaters as a series resistor for economically integrating a low voltage, direct current, small motor, for driving the air wheel or blower of the air moving means of the hair dryer.
And still another object of this invention is to provide a combination of electrical elements which will produce an inexpensive construction, and an efficient assemblage of electrical components, for a hand-held hair dryer and having a capacity of providing up to 500 watts power.
To meet the foregoing objects there are provided molded, dished, parts that are joined together to provide a lightweight casing mounted at one end of a handgrip, the casing including a reflector therein, with an infra-red radiation source supported on the casing and arranged in a ring, in such a manner that the radiation of the infra-red radiator is amplified, or enhanced, by the reflector, and providing centrally of said casing a small, lightweight, electromotor that drives an air wheel, or propeller fan, that is positioned in a region between the reflector and the ring-like, infra-red source. The casing is provided, on its backside, with an air entry lattice, or grille, and on its frontside with a blow opening of large diameter, in which blow opening there is positioned a molded part that is shaped to integrally provide a front lattice, or grille, a central motor holder, and a rearwardly extending radiation-blocking sleeve positioned between the ring-like, infra-red source and the motor holder to provide therebetween a space or channel for flow of air therethrough.
Further objects and advantages will become known to a person skilled in the art from the following description of the invention having reference to the drawings of a preferred embodiment wherein: